Nurses Role in Medication Administration

Last updated: Monday January 06, 2003

Much of nursing practice involves decisions about:

administration

effects

side effects of drugs

Implications for Nursing Practice

Dependent practice - by Prescription
Interdependent practice - MD and RN consult
Independent practice - nurse prepares and administers monitors for side effects patient teaching

Nurse is responsible for what, how, when, and how much is given

Must question orders that seem incorrect or inappropriate

Nursing Implications

Responsible for understanding:
expected effects
untoward effects
dosages and protocol to give
actions to take in event of untoward reaction

Nursing Implications

DRUGS ARE LETHAL WEAPONS

THERE IS A FINE LINE BETWEEN CORRECT DOSES AND LETHAL OR TOXIC EFFECTS

Definitions

Pharmacokinetics-
What the body does to the drug
Pharmacodynamics-
What the drug does to the body

Medication orders

Prescription from M.D.
sometimes nurse practitioner (CRNP) or physician’s assistant (PA) both may need to be co-signed by MD

Types of med orders

standing - until cancelled or d/c by agency policy or for particular symptoms
prn - as needed (e.g. for pain)
single order - once, at a certain time
stat - immediately; once only

Essential parts of med order

client name
date/time order written
name of drug (generic or brand)
dosage (metric or apothecary)

amount
frequency

route
signature

Routes of Administration

oral
sublingual
buccal
rectal
topical
transdermal
inhalation
Parenteral
subcutaneous
intramuscular
intradermal
intravenous
intraarterial

Medication Administration
5 "rights"

client
medication
dosage
route
time

within 1/2 hour

Safe medication administration

5 "rights"
3 checks

reach for container or unit dose packet
right before pouring or opening
as return container - BEFORE administering

Administering any meds

You prepare, you give.
give within 30 minutes of time ordered
identify client (check name band)
explain to client
if client questions drug or dose - STOP
observe client take med

per agency policy
antacids, lozenges

document after giving (or refused)
monitor and evaluate client response

Administering oral meds

check if NPO, intact gag and swallow reflex
position patient properly
provide straw as needed
crush or mix in food (e.g. applesauce) prn

Administering parenteral meds

Select appropriate size (guage) and length of needle

guage - 18 thru 27
length - 1/2 to 2 inches

Select appropriate size syringe

1 - 3 ml

Use aseptic technique
Select appropriate site - IM, SQ, ID

Administering parenteral meds

Don disposable gloves
Cleanse site
Inject quickly - 90⁰
Aspirate (not heparin, intradermal)
Inject medication
Dispose in puncture-resistant container without recapping
Record
Evaluate

IM Site Selection

Dorsogluteal (buttock)
Ventrogluteal (hip)
Vastus lateralis (lateral thigh)
Rectus femoris (anterior thigh)
Deltoid (arm)

Needleless Systems/Protected Needles

recessed IV connectors
blunt cannulas
needles sheathed in plastic guard
retractable needles

Measurement Systems

Apothecary

Basic unit weight - grain (gr)
Basic unit volume - minim (m) (@ drop)
1 gr = 1 m = 1 drop
written with Roman numeral gr ii
Others: dram (z ) ounce pint, quart, gallon

Household

drop (gtt) 1 minim
tsp (t) 4-5 ml (z ) @ 60 gtts
3 tsp = T (15 ml)
2 T = 1 oz (30 ml)
1 c = 8 oz

Metric

based on units of ten (decimal system)
3 basic units measurement
length - meter (m or M; cm; mm)
volume - liter (l or L; ml)
weight - gram (g or Gm; mg)

Volume and Weight Equivalents

Basic principles of math

Roman numerals i, ii, iii, iv, v, x gr i, gr v 1/2 = ss
Fractions
Decimals based on tenths

R of . < 1.0 (0.78)
L of . > 1.0 (12.0)
Multiply by 10s, 100s, 1000s - move decimal point
Add or subtract keep decimals lined up

Ratio and Proportion
ratio - express relationship by division 1/3 or 1:3
proportion - 2 equal ratios 1/3 = 3/9 or 1:3::3:9
Product of means always = product of extremes

use to solve for x

2 = 8 2:4::8:x 4 x

2 x = 32
x =

What you KNOW What you NEED

DOSE HAVE :: DESIRED DOSE Quantity on hand Quantity to give

Rx: Demerol 75 mg IM stat
Have: Demerol 100mg/ml in vial

DOSE HAVE :: DESIRED DOSE Quantity on hand Quantity to give

100 mg :1ml :: 75 mg : x ml ( 100 = 75 ) 1 x

100 x = 75
x = ml

Rx: Cardizem 90 mg po qd
Have: 60 mg / tab

DOSE HAVE :: DESIRED DOSE Quantity on hand Quantity to give

60 mg :1 tab :: 90 mg : x tabs ( 60 = 90 ) 1 x

60 x = 90
x = tabs

Rx: Lasix 40 mg IV push stat
Have: 10 mg / ml

DOSE HAVE :: DESIRED DOSE Quantity on hand Quantity to give

10 mg :1ml :: 40 mg : x ml ( 10 = 40 ) 1 x

10 x = 40
x = ml

Rx: Amoxicillin 250 mg po q 6h
Have: 500 mg/5cc

DOSE HAVE :: DESIRED DOSE Quantity on hand Quantity to give

500 mg : 5 ml :: 250 mg : x ml ( 500 = 250 ) 5 x

500 x = 1250
x = ml

Converting between systems of measurement

Rx: ASA gr v po qd
Have: ASA 325 mg tabs
How many tablets will you give?
Use conversion factor - gr and mg

Conversion factor?
1 gr = 65 mg (KNOW)

What you KNOW What you NEED

UNKNOWN/NEED ?
5 gr = x mg

What you KNOW What NEED TO KNOW
1 gr = 65 mg :: 5 gr = x mg
(1) x = (65) (5)
x = 325 mg (There are 325 mg in 5 gr)
How many tablets will you give?

325 mg = 325 mg (5 gr) 1 tab x tabs
325 x = 325

May need 2 steps

Rx: Lithium gr x po t.i.d.
Have: Lithium 300 mg/capsule
How many caps will you give?
Conversion factor: 60 mg = 1 gr
60 mg : 1 gr :: x mg : 10 gr x = 600 mg (not caps)

NOW 300 mg : 1 cap :: 600 mg : x caps 300 x = 600 x = 2 caps

Drugs measured in Units

Insulin 100U/ml

Heparin 10-20,000U/ml

Penicillin 400-800,000U/ml

Rx: 5,000U Heparin sq q 12h
Have: 20,000 U/ml
Can use Desired X Amount Have

5,000U X 1ml = 20,000U

Give = 1 or .25 ml 4

Rx: 40U NPH Insulin sq q AM
Have: 100U/ml in vial (U-100; U-50)
Use U-100 syringe

D X Amt 40U X 1ml = 0.4 ml H 100U
OR ratio/proportion 100U:1ml :: 40U: x ml

100 x = 40

x = 0.4 ml

Drugs provided in powder form

Must be reconstituted for injection
Rx: aqueous penicillin G 500,000 U IM Have: 5,000,000 U in dry powder in vial
How many ml will you give?
TRICK QUESTION!!
You need to reconstitute - add diluent.
Follow manufacturer directions.

Reconstitution instructions:

Add for U/ml 18 ml 250,000 8 ml 500,000 3 ml 1,000,000

How much diluent will you add?

(sterile water,NaCl)

You want to give 500,000U per dose.

Add 8 ml diluent = 500,000 U/ml

KNOW = UNKNOWN/NEED

500,000 U = 500,000 U 1 ml x ml
500,000 x = 500,000
x = ml

IV fluids

MD orders type solution amount " time of infusion

medications to be added

to continuous infusion

to intermittent infusion

(IVPB)

as bolus dose

Calculating milliliters per hour

Rx: 1000 ml NSS to run over 6 hours

total volume = ml/hour total time in hours

1000 = 166.6 ml/hr 6
Round off to 167 ml/hr

Calculating Drops per Minute

Rx: Administer 1000 ml D5W every 8 hr. Drop factor is 15 gtt/min

total volume x drop factor = gtt/min total time (in minutes)

1000 ml x 15 = 15000 8 x 60 480

= 31.25 gtt/min

Round to 31 gtt/min

Common IV Drop Factors

Macrodrip 10gtt/ml 15 gtt/ml 20 gtt/ml

Microdrip 60 gtt/ml

Rx: Kefzol 1 g IVPB q 6 h

(Mix in 50 ml D5W. Infuse over 20 min.)

Drop factor is 20 gtt/ml

Kefzol supplied as 500mg/ml.

How many ml will you add to 50 ml bag?

500 mg = 1g

1 ml x ml

500 mg = 1000 mg

1 ml x ml

500 x = 1000

x = ml

How many drops per minute will you run the Kefzol so it is absorbed in 20 minutes?

50 ml X 20 (drop factor) = 20 (time in minutes)

1000 = 20

Run at 50 gtts/min

Tips from Errickson & Todd

Write out units of measurement; must appear in same order

e.g. 60 mg = 90 mg (60mg:1tab::90mg:x tabs) 1 tab x tabs

line up decimals

Re-check if odd answer e.g. 25 tablets !!
Calculator only as good as your set-up

Names of drugs

Generic - assigned
Official - as listed

USP, NF

Chemical - describes composition
Trade or brand name
Hydrochlorthiazide
aspirin

acetylsalicylic acid

Bayer

Hydrodiuril

Classifications of Drugs

According to:

body system - cardiac
clinical indication/effect - antibiotic
composition - chemical
symptom relieved/purpose - relieve pain

Kinds of Drug Actions

Therapeutic effect - desired
Side effect - secondary or unintended

therapeutic should outweigh side effect

Kinds of Drug Actions

Adverse effects (FDA MEDWATCH)

Iatrogenic disease

cumulative - drug level builds up
drug tolerance- larger doses needed for same effect
idiosyncratic - unexpected, peculiar

(e.g. elderly)

drug allergy - minor to serious immune reaction

anaphylactic reaction - sudden, life-threatening

Drug Interactions

Combined effect of 2 or more drugs alters effect of one or both:

antagonistic/inhibiting effect - lesser

antacids/milk with Tetracycline

synergistic/potentiating effect - greater

e.g. alcohol and barbiturates

Demerol and Phenergan

Drug Standards

To predict effect based on consistency,

uniform quality

Pure Food and Drug Act (1906) - must be listed in

US Pharmacopeia (USP)
National Formulary (NF)

Drug Laws

Federal Food, Drug, Cosmetic Act (1938)

extensive testing of new drugs

Comprehensive Drug Abuse Prevention

and Control Act (1970) (Controlled Substances Act)

must have prescription for controlled substances:

narcotics, amphetamines, barbiturates, tranquilizer

Harrison Narcotic Act

controlled substances must be kept in double-lock system

State Nurse Practice Acts

Prescriptive rights for NPs
Administering drugs IV push

Question and/or refuse to give incorrect or contraindicated order

Decimal Point Dangers

Rx: dexamethasone .10 mg IV q 12h x 72 h
Transcribed as 10 mg
Avoid error by:
writing as dexamethasone 0.1 mg don’t use "0" after decimal point
if 1.0 mg - write "1 mg" instead